PROBLEM

A new copper mine is to be started$-$up$.$ A $60m$ wide orebody outcrops on surface and dips at

$85$ degree towards the south. The orebody is economic up to $200m$ below surface. From

$200m$ further deep the grades are very poor. Open pit has a limit of $150m.$ below that an

underground mine has to take over. Underground equipment will include LHD$\text{'}$s$,$ drill rigs,

some of which are at most $4m$ wide and $5m$ high. A representative $log$ of the host rock is

shown.

Given that:

$3$ joints sets are prevalent this environment. The joints are mostly curved and slicken$-$

sided, with some fine material infilling.

$RQD=60$

The host rock is slightly moist and wet in some locations

$K$ ratio $=1\mathrm{.}6$

Standard safety factor for the mine is $1\mathrm{.}3$ as a matter of policy $($ be it dumps, slopes,

underground support, etc.$).$ A company has requested you to perform a geotechnical design

feasibility. That means:

PART A

$$ Work out rock mass ratings.

$$ Determine stable slope angles

$$ Determine potential for wedge formation stability thereof

$$ Determine underground self$-$supporting span

$$ Underground support and pattern.

PART B

Given that the cost of waste removal is $R\frac{30}{m^3},$ ore material sells at $R\frac{1000}{?}$ ton. Determine

the percentage gain in the open pit as a result of increasing overall slope angle by $1$ degree.

PART C

If the preferred underground method is block caving, determine the suitable dimensions for

rectangular undercuts for caving.

PART D

The only available space for top$-$soil and softs dumps is $150m150m.$ Design suitable

dumps architecture in line with company policy.

Please note that this is a geotehnical engineeing module. Also give the aim, background and conclusion for this assignment.